title: HPr proteins of different microorganisms studied by hydrogen-1 high-resolution nuclear magnetic resonance: similarities of structures and mechanisms.
abstract: The HPr proteins of Streptococcus lactis, Streptococcus faecalis, Bacillus subtilis, and Escherichia coli were studied by 1H NMR at 360 MHz. The "active-center" histidines of all HPr proteins are characterized by a low pK value between 5.6 and 6.1 and similar spectral parameters. Phosphorylation of the histidyl residues leads to an increase of the pK value of 2-3 units and spectral changes characteristic for N-1 phosphorylation of the histidyl ring. The spectra of the HPr proteins of S. lactis, S. Faecalis, B. subtilis, and Staphylococcus aureus reveal many similarities, whereas the spectrum of the E. coli protein is different with exception of the active-center histidine. The HPr protein of S. lactis is formylated at its terminal amino group.
mesh_terms: D001412:Bacillus subtilis / Q000378:metabolism; D001426:Bacterial Proteins; D001665:Binding Sites; D005075:Biological Evolution; D002352:Carrier Proteins / Q000378:metabolism; D013293:Enterococcus faecalis / Q000378:metabolism; D004926:Escherichia coli / Q000378:metabolism; D006639:Histidine; D006863:Hydrogen-Ion Concentration; D013294:Lactococcus lactis / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System; D013045:Species Specificity
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D006639:Histidine; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System; C030182:phosphocarrier protein HPr